Overview of 5G Technology, How it Works, and Current Deployments
5G is the fifth-generation wireless technology with the potential to transform communication systems. It offers higher speeds, low latency and other benefits that will open up and power a wide range of existing and emerging technologies.
The 5G network delivers faster connections with much larger capacity and low latency (less than 1 millisecond compared to 30 milliseconds for 4G and 100 milliseconds for 3G).
Providers promise theoretical speeds up to a maximum of 10Gps, which is about a hundred times the 100Mbps 4G peak speed. Although the actual speeds will vary according to a range of factors and are unlikely to reach the maximum, the technology will offer a much better experience and opportunities than existing wireless technologies.
Today, a good number of technology companies and providers are developing and deploying these networks either in trial or commercial setups. Among the many possible use cases, mobile broadband deployment is currently leading and enabling high-speed data transfers for mobile devices.
5G Applications
5G is a technology that will transform wireless communications in many ways. Unlike prior wireless technologies that focused on mobile broadband only, 5G has additional applications.
Fast 5G networks support IoT, machine-to-machine communications, remote medical care, autonomous vehicles, augmented reality, and other emerging technologies that require real-time control and reliable connectivity.
Other industries that will benefit from 5G include media content distributors and providers such as Hulu, Netflix, and others. New data transfers will allow users to download huge files in a few seconds. This benefits users by reducing download time and battery usage of the already energy-constrained mobile phones and tablets.
Currently, there are three main application categories;
1. Enhanced Mobile Broadband (eMBB)
This category targets mobile users and will enable better broadband access everywhere, including densely populated areas, moving vehicles, etc. Networks in this category offer enhanced connectivity, higher capacity, and better user mobility.
2. Massive Machine Type Communications (mMTC)
Use cases in this category include the Internet of Things; where 5G technology offers a high capacity and reduced latency, both of which are ideal for the growth of IoT applications.
3. Ultra-reliable, Low-latency Communications (URLLC)
This includes mission-critical applications that require real-time control of devices. Typical areas are vehicle-to-vehicle communications, industrial robots, autonomous driving, remote medical care, robotic-assisted surgery, augmented reality, virtual reality, and more.
How Does 5G Work?
5G networks, just like older generations, comprise of several cell sites with sectors that send coded signals. Each cell site connects to the main network backbone through fast wireless or a wired backhaul connection.
The 5G network uses OFDM encoding, just like 4G LTE, but more efficiently to provide better speeds. However, by design, the air interface for 5G has more flexibility and lower latency than LTE.
The main reason why 5G is faster is the larger channels it uses. For example, the majority of 4G channels are 20MHz channels, and these are usually bundled together to provide a maximum of 160MHz at a time. On the other hand, 5G has channels which can be as high a 100MHz, and a potential to combine several of them up to 800 MHz.
In practice, these 5G base stations use less transmit power than 4G systems. This is due to energy-efficient advanced radio and core architectures that optimize the EMF levels based on the requirements. Also, the 5G network design allows the stations to control their power and use the least possible to achieve satisfactory communication.
5G Frequencies
There are three different frequency bands for the 5G networks; the low and mid-band spectrum at the sub-6GHz range, and the high band at the millimeter-wave, 24–100GHz, frequencies.
Each band has a unique infrastructure and application requirements. As can be seen, some 5G networks utilize the sub-6GHz spectrum, which the existing LTE networks use. On the other hand, the high band 5G uses millimeter waves which were not being used and promises to provide more bandwidth and faster speeds.
Low-band 5G uses the frequencies below 1GHz. It has narrow and fewer channels since 4G networks use the same region. Generally, the low-band offers low-speed 5G connections and has typical channels averaging 10MHz width. This makes it suitable for long-range, low data rates, and narrowband applications such as machine-to-machine communications. (mMTC).
Generally, the frequencies below 1GHz are common in Macro base stations.
Mid-band 5G uses the frequencies in the 1–6GHz range and can reach a distance of about half a mile. The majority of the mid-band 5G networks offer 100MHz channels and carries the largest amount of 5G traffic in most countries. This region is suitable for LTE bands and similar applications that require bandwidths in the order of 100MHz.
In practice, the 5G networks will utilize 2.5GHz band 41 and the 3.5GHz bands 42+43 for eMBB applications.
High-band 5G lies in the 20- 100 GHz region where there is lots of unused spectrum. However, the network has a shorter range than the other two. The band uses larger channels of up to 800 MHz at a time; this gives it the ability to offer fast speed connections and can transfer huge amounts of data. Before 5G, the band has been used for backhaul applications where they connect the base stations to the internet links.
Because the waves cannot travel long distances they have not been used for mobile devices. However, with 5G, the Telcos are using many smaller, low-power base stations targeting many mobile users near the cells, and more powerful for longer distances and URLLC applications such as autonomous driving.
Influence of 5G Frequency on Speed and Coverage
The 5G frequency band impacts the speed, power of the wave, and the distance it travels. At higher frequencies, the signals will travel faster, but only for shorter distances.
Today, there are many unused airwaves in the high band, and this makes it one of the most attractive. However, it is complex and has challenges such as the short distance. On the other hand, lower frequencies are slower but will travel long distances.
In typical applications, providers may use the higher frequencies in areas such as cities where there are many devices or demand for huge amounts of data transfers. However, the high frequencies mean shorter wavelengths that cannot travel long distances. Objects along the waves’ path can also block them; hence preventing them from traveling through walls and other structures. Installing many nodes will ensure that the users can access the network as long as they are within the coverage area.
Generally, for a device to access the mmWave signals, it must be very close to the 5G nodes. These are small cells that do not require large supporting infrastructure and providers can install them on lamp posts and other common structures in metropolitan areas.
Because of the need to have nodes that are close together, the 5G millimeter-wave band is unsuitable for rural areas or locations with few cell towers, support structures, or buildings. As such, the low-band 5G networks, which have a longer range, will be useful in areas without a direct line of sight.
To ensure fast and widespread signals, most 5G deployments will combine the low-, mid- and high- bands. The choice of the band will depend more on the location, application, and existing structures.
For example, companies such as T-Mobile have deployed mmWave in various cities, as well as low band frequency networks for nationwide coverage. This gives them the ability to serve about 5000 cities and towns, as well as several rural areas falling under the coverage area.
Countries and Companies Leading in 5G Deployment
5G equipment manufacturers and service providers spread across different countries are at various stages of developing and deploying 5G technologies. Since there are different components that make up 5G technology, no one company can excel in all of them. The following are some of the companies leading in various fields.
Leading countries in 5G network deployments
- South Korea — South Korea: SK Telecom and Korea Telecom
- United States of America -AT&T and Verizon, Sprint/T-Mobile US Inc.
- Germany — Vodafone and Deutsche Telekom
- United Kingdom — EE, Vodafone UK, Three UK, and O2 UK
- China, — China Telecom (CHA), China Mobile (CHL), and China Unicom (CHU)
Other upcoming 5G countries include Japan, Turkey, Switzerland, Norway, Denmark, Iceland, Sweden, and Finland.
Manufacturers
- 5G user devices — Samsung
- 5G chipsets Qualcomm
- 5G infrastructure — Ericsson, HPE, and Huawei
5G carriers
- Asia — China Mobile, China Asia, and SK Telecom- South Korea
- Europe –EE, Deutsche Telekom, and Vodafone.
- North America and Canada — T-Mobile/ Sprint, Verizon and At&T
Intellectual property and patents
- Qualcomm
- Huawei
Challenges and Concerns About 5G
Today, there are several Telcos and service providers who are continuously deploying 5G systems on trial or commercial use, but we are yet to see a global deployment due to various challenges. The technology is still undergoing developments and there are issues such as standards and others to address, in addition to developing the right 5G infrastructures and devices.
Some of the challenges include high cost, few 5G products, overheating on some devices, no global standard, health concerns, and more.
Other challenges include
· Spectrum allocation and auctions
· Covering the hard to reach areas
· Barriers due to competition
· Security across different bands of the spectrum
· Device support
Costly 5G Infrastructure
To increase coverage, the service providers must deploy a large number of 5G towers close together and with existing technologies, and this results in higher deployment costs and complexity.
It is unlikely that 5G will replace 4G entirely. Already, the 4G coverage is not as widespread, especially in remote and less commercially viable locations where the best consumers get is 3G. The cost of 5G infrastructure is high, and service providers will need to justify the need to replace the 4G system which in some counties and locations is still less than three years or thereabout.
5G Health Concerns
Consumers and lobby groups worry that exposure to the high-frequency RF signals will lead to certain health problems such as skin cancer. Because of the small wavelengths, the skin will absorb the RF energy and there are fears that this can cause cancer.
Experts argue that while there might be a small increase in the exposure to RF energy, the effect will be insignificant. All the 5G frequency ranges fall within the non-ionizing bands and well below the dangerous levels as specified by ICNIRP.
Currently, there is no scientific evidence to prove that the 5G electromagnetic waves can lead to health issues. However, there is a need to study and determine the short- and long-term effects of the waves, and whether they are dangerous to human beings, either directly or indirectly.
Conclusion
Countries and companies across the globe will need to overcome numerous challenges as they plan or prepare to introduce or implement 5G technologies. These range from competition and regulations (that vary from country to country) to resources and money to build and support the infrastructure.
Despite the challenges, which are normal for every new technology, several companies are working hard to ensure the success of 5G.
